additional CSS and JS files being loaded by the browser. While it's not strictly a problem, many page speed tools will complain about it!

The workaround is to set:

session.timeout.warning=0
session.timeout.auto.extend=true

however this will also affect logged-in user which may not be acceptable

The proper fix should be to distinguish logged-in users from guests and only use the values from the properties file for logged-in users while automatically extending the session (without any notifications) for guest users!